Types of dementia

What is dementia?

Dementia is an umbrella term for a number of progressive conditions affecting memory, thinking, problem-solving and language. It is caused by diseases which damage brain cells and interfere with the normal workings of the brain.

Everyone will experience dementia differently, depending on the cause, on which parts of the brain is affected as the condition progresses, and their own personality and circumstances.

Different types of dementia have different causes. Alzheimer’s disease is the most common cause, followed by vascular dementia, dementia with Lewy bodies and fronto-temporal dementia. There are a large number of less common causes of dementia and some people have more than one form at the same time, known as ‘mixed dementia’.

According to Alzheimer’s Research UK there are around 820,000 people living with dementia in the UK. The majority are older people, and incidence increases with age, with one in 20 over the age of 75, and one in five over the age of 85, affected. However it is possible for younger people to have dementia, and dementias that are diagnosed before the age of 65 are known as 'early-onset'.

In Wiltshire, there are estimated to be just over 7,000 people living with dementia.

Alzheimer's disease

Alzheimer’s disease is the most common form of dementia. It was first observed by Dr Alois Alzheimer in 1901.

It is a progressive illness caused by chemical changes in the brain that allow abnormal proteins to build, forming clumps known as plaques or tangles. The plaques are usually first seen in the area of the brain that makes new memories, and memory loss, or difficulty remembering words, is often one of the earliest symptoms.

Typical symptoms of early Alzheimer’s include:

Regularly forgetting recent events, names and faces

Regularly misplacing items or putting them in odd places

Confusion about the time of day

Disorientation, especially away from normal surroundings

Getting lost

Problems finding the right words

Mood or behaviour problems such as apathy, irritability, or losing confidence

As the disease progresses communication, perception, orientation and mobility can be affected as the brain's ability to control the body declines.

Treatment

There is currently no cure for Alzheimer's disease. However, drugs are available that can slow down symptoms in some people.

Aricept, Exelon and Reminyl work by maintaining levels of acetylcholine in the brain. Side-effects are usually minor but may include diarrhoea, nausea, insomnia, fatigue and loss of appetite.

A fourth drug, Ebixa (trade name for the drug memantine) works in a different way from the other three and is the only drug that is recommended for people in both the moderate and severe stages of Alzheimer's disease. Side-effects may include dizziness, headaches and tiredness, and - rarely - hallucinations or confusion.

However, knowing more about the disease and understanding why the changes are happening, can help the person and those around them to cope better. Coping strategies include slowing down the pace of life, following routines, using clear communication and focusing on what the person affected can still do and enjoy doing, rather than on their limitations.

Vascular dementia

Vascular dementia is the second most common form of dementia. It is caused by a reduction in blood supply to the brain.

It may occur as a result of a stroke or a series of small or mini strokes (TIAs) which can affect any part of the brain. Alternatively it can be caused by a gradual hardening of the blood vessels deep in the brain, typically affecting parts that are important for attention, memory and language.

Symptoms of vascular dementia can appear gradually or suddenly depending on the cause. They include:

Becoming slower in thinking

Disorientation, especially away from normal surroundings

Difficulty finding words

Memory problems and regularly misplacing items

Becoming more emotional

Difficulty walking or a change in the way a person walks

Treatment

The Azheimer's drug treatments are not normally prescribed for people with vascular dementia, but may be useful in a 'mixed dementia' where there is both Alzheimer's and vascular dementia present. Although the brain damage that causes vascular dementia cannot be reversed, it may be possible to slow the progression of the disease by:

Taking medication to treat any underlying conditions, such as stroke, high blood pressure, high cholesterol, diabetes or heart problems

Lewy Body dementia

Dementia with Lewy bodies is a rare form of dementia caused by small clumps of protein that build up inside nerve cells in the brain, damaging the way they work and communicate with each other. These are named Lewy bodies after Dr Frederich Lewy, who first identified them. Lewy bodies are also present in some forms of Parkinson's disease.

Symptoms include:

Hallucinations which often involve people or animals

Parkinson’s-type symptoms including slow movement and stiffness in the limbs

Movements during sleep and vivid dreams

Symptoms similar to Alzheimer’s, including memory loss and disorientation

Fainting and falls

Marked variation in alertness and confusion, which can fluctuate from hour to hour or day to day

Treatment

Like other types of dementia there is no cure for LBD. Some of the Alzheimer drugs may be suitable for people with Lewy body dementia, but particular care has to be taken by doctors as some are unsuitable.

Coping strategies include understanding as much as possible about the disease and the changes it can bring, particularly that visual disturbances may be very real to the person affected, even though others cannot see them. Rehabilitative support, such as physiotherapy, occupational therapy and speech therapy can also be helpful.

Fronto-temporal dementia

A less common cause of dementia, and one that often affects people in younger age groups. It includes a range of conditions in which there is damage is to the front and sides of the brain and affects personality, emotions, decision-making, speech and language. It used to be known as Pick’s disease

Symptoms can include:

Personality changes, such as loss of inhibition, apathy or inappropriate behaviour of which the person is often unaware

Loss of emotional warmth and empathy for others

Decline in language abilities – including difficulty getting words out or problems with understanding words and names

Memory problems. Although day to day memory remains intact in the early stages, communication difficulties mean the problems seem more severe

Treatment

Alzheimer’s drugs such as Aricept are not normally prescribed and can may occasionally make symptoms worse. Speech therapists may be helpful for language problems.

Knowing more about the disease and understanding that it it this which is the cause of behaviour changes, can help the person and those around them to cope with the disease. Coping strategies include avoiding confrontation and working round obsessions rather than trying to change the person's behaviour.

Music for the Mind, (formerly Singing for the Brain) is uplifting and hugely beneficial for people living with dementia. We run 11 groups in Wiltshire - and you don't need to be a good singer to take part.